His favourite job interview question is a twist on the classic “tell me your greatest weakness” question, and it also proves useful in the development process for the candidates that get hired.

McCann told Business Insider that he asks candidates to imagine a scenario:

The candidate is hired and works at 1-800 Flowers for a year. Jim and his brother Chris, the company’s CEO, are relaxing at Chris’ house, where he’s uncharacteristically treating Jim to a nice bottle of wine, and they’re candidly discussing the candidate’s performance. What are they talking about?

Specifically, McCann asks candidates, “What am I going to see in your behaviour a year from now that you wish you had told me today?“

There was a guy McCann hired for the tech team, for example, who told McCann, “People think I’m a royal pain in the arse.” It turned out to be true, McCann said, laughing. This employee performed well and worked hard, but he irritated his coworkers with his impulsive, stream of consciousness replies to team-wide emails.

At one point, McCann took this employee aside and reminded him of what they talked about in his job interview, and proposed to him a fix for the employee’s problematic email habit. Before this employee could reply to a non-urgent email, he had to wait an hour, to avoid reacting emotionally. The employee agreed and everyone benefited, McCann said.

More recently, McCann hired a young employee who told him in her interview that she had difficulty setting priorities. To check in with her progress after she had been with the company for some time, he asked her to show him a list of projects she was working on so that they could arrange them in order of importance.

“And she said, ‘Since I told you that that was something that I didn’t think I was good at, I think I’ve gotten pretty good at it — I’ve already ranked them!'” he explained. The seed was planted back in her job interview, allowing her to find a way to work more efficiently as soon as she joined the company.